The Science of Natural Selection
by WinterD
Summary: The Time War didn’t just destroy the Daleks and the Time Lords. There were other species that were casualties of war. Some died off quietly. Some are fighting back for survival.


Title: The Science of Natural Selection

Rated: PG-13

Summary: The Time War didn't just destroy the Daleks and the Time Lords. There were other species that were casualties of war. Some died off quietly. Some, like the Gelth and the Nestene Consciousness, are fighting back for survival.

Characters: Rose Tyler, the Doctor, and Jack Harkness

Disclaimer: I own nothing. RTD, the BBC, and others own all things Doctor Who. Point is, I don't. pout

AN: Written for the Rose Tyler Ficathon. lefemmedarla wanted 1) Jack Harkness and/or Ninth Doctor, 2) Mention of Gallifrey, and 3) An adventure on an alien planet. Hope they like it.

Special thanks to my beta Charlotte.

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_Zero_

Rose ran.

Her bare feet slapped against the too cold linoleum floor, each step echoing far too loudly in the empty hallway. Each breath she drew was sharp and shallow, and more than once she wanted to stop and cough until she couldn't breathe any longer, but she knew she couldn't. If she stopped, they'd catch her. If they caught her, she knew she was dead. So she ran.

One of the doors in the corridor squeaked open and a woman dressed in an odd uniform stepped out. The stark and stiff white dress stood out against the metallic bronze shade of her skin reminding Rose of a copper coin in a fresh pile of snow. Startled, the woman took a step backwards and placed her hand over her heart as she ran by. Rose wasn't sure, but she thought the woman yelled for help.

Over the loudness of her footsteps and through the pounding of her heart in her ears, she could hear the others. Though she was sure they were yelling to one another, their voices were muffled and distant, but she knew they were close. If she could hear them, they were close. Too close.

The hallway ended and turned into another. Rose tried to turn with it without slowing down, but her feet slid and twisted under her. Pain exploded from her ankle and shoulder as she first collided against the wall then fell to the ground in an ungraceful heap of oddly angled limbs. Groaning, she tried to scramble back to her feet, only to fall once more. Her ankle throbbed painfully in protest of her weight, but she had to ignore it, just like tightness of her chest and the forceful chill that shook her damp body. She had to get away. She just had to.

Finally managing to scramble to her feet, she glanced over her shoulder as she began to limp away. One of them was running towards her, yelling her name. But there was only one. So where was the other -

"Gotcha."

When he appeared before her from a connecting corridor, she tried to slide to a stop and duck away from him, but her injured ankle caused her to stumble instead. She crashed into him just like she had crashed into the wall, and he remained just as steady. Before she had even had time to straighten herself up, he wrapped his arms around her waist and held her tightly with her back against his chest.

"No! Let go!" she yelled in voice that she was sure was loud enough to be heard all the way to the TARDIS. In fact, maybe they heard her.

He hand managed to pin her left hand in his grasp, but her right arm remained free so she put it to good use, clawing deeply into his arms. Rose heard him yelp from the surprised pain and she felt a certain amount of satisfaction from that. He were going to hurt her, well she was going to hurt him right back.

It wasn't this one that she was so worried about, though. The other one, he was the one that could hurt her so easily with his burning, cold touch.

"Ow! Hey, stop!" he said as she squirmed and vainly fought against his grip. "Rose, stop! It's me. It's Jack."

Jack - no, not Jack; Jack wouldn't hurt her like he was - readjusted his grip on her, determined to not let her break free.

"Let me go!" Her plea sounded a bit hysterical, even to herself, but she had to get away. She had to find the Doctor and Jack. The real Doctor and Jack. Not these doppelgangers. Or, if she dared think it, these Gelth.

"Hold onto her, Captain," the Doctor - no, no, no; not her Doctor - said, running towards them. Behind him was the woman in white, one of the nurses.

"I'm trying," Jack said. "Damn, Doc, she's burning up."

Growling, Rose pulled her fingernails out of his arm and kicked at the Doctor. He was able to avoid her leg, but when he came close again, she managed claw him across the face. Thin lines of blood appeared along the three scratches she left on his cheek, but he didn't so much as flinch. Instead, he grabbed her free wrist and stepped forward to pin her more against Jack. She tried to swallow the agonizing howl of pain that his cold flesh against her skin caused, but it came out as a whimpering sob instead. That time, he did flinch, but remained determined.

"Hold her still," the nurse said, pulling something from her apron pocket. The Doctor started to protest, but she felt a sharp pinch before he could stop her. Slowly, her body began to become heavy and, though the need to flee was still strong, the need for sleep started to take over.

"What did you give her?" the Doctor asked and she became slack in his and Jack's grip.

"Only a mild sedative. The same as we did before," the nurse said. "No harm will come to her from it."

Reaching up, the Doctor pulled up one of her eyelids, frowned, and then did the same with the other eye.

"She has the Cat's Eyes," the nurse said solemnly. "There is nothing you can do for her now."

Cat's Eyes? That was bad, wasn't it?

Letting her eyelid drop, the Doctor moved away and said, "You lot might not can, but you're not me. Jack."

On the edge of consciousness, Rose felt Jack pick her up and start to follow the Doctor. No. No, she can't go with him. She had to find the Doctor - the _real_ Doctor. These imposters were going to hurt her.

"You cannot take her!" the nurse shrieked. "She is Touched! She will infect others if you - Doctor!"

The Doctor, of course, ignored her, as did Jack.

"Let me go," Rose said quietly.

The fake Jack's steps faltered, but he just readjusted his hold on her and continued after the Doctor. "Don't worry, sweetheart. We'll fix you."

They'll kill her. That's what she knew they would do.

She wanted to fight him. She wanted to break free from him and run as fast as her legs could take her, but she was finding it difficult to do anything at the moment, and that included fighting off the heaviness of sleep. As she slipped into unconsciousness, Rose found herself trying to remember what it was she had found so charming about Ishastine in the first place.

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TBC


End file.
